Inductors are used in a wide variety of integrated circuit applications including voltage regulators such as switching power converters. An inductor is a conductor that is shaped in a manner to store energy in a magnetic field adjacent to the conductor. An inductor typically has one or more “turns” that concentrate the magnetic field flux induced by current flowing through each turn of the conductor in an “inductive” area defined within the inductor turns.
Inductors have been implemented in integrated circuit packages but they may have several drawbacks. They have typically been made by forming helical or spiral traces in conductive layers (such as in conductive substrate layers) to form inductor turns. The traces may or may not be coupled to traces in adjacent layers in order to achieve higher inductance and/or current capability. Unfortunately, they can consume excessive trace layer resources and may not provide sufficient current capacity without unreasonable scaling. In addition, because their inductive areas are substantially parallel with respect to other trace layers in the substrate and circuit die, they can have unfavorable electromagnetic interference (EMI) effects on other components within the integrated circuit and/or their inductor characteristics can be adversely affected by adjacent conductors within the substrate. Accordingly, a new inductor solution is desired.